Can you take januvia and metformin together?
Yes. Januvia (sitagliptin) and metformin are both oral medications for type 2 diabetes. They have different mechanisms and no known interactions, making them safe to use together. Combination therapy is common when metformin alone does not achieve target blood glucose levels. They are also available together as Janumet (immediate‑release) and Janumet XR (extended‑release).
What is Januvia?
Januvia is a DPP‑4 inhibitor used with diet and exercise to improve glycemic control in adults with type 2 diabetes. Not for type 1 diabetes or diabetic ketoacidosis. Avoid in severe kidney impairment or dialysis.
What is metformin?
Metformin is a biguanide that lowers hepatic glucose production, reduces intestinal absorption of glucose, and improves insulin sensitivity. Approved for adults and children ≥10 years with type 2 diabetes, alongside diet and exercise.
Side effects of Januvia
- Headache
- Upper respiratory symptoms (sore throat, runny/stuffy nose)
- Sore throat
- Hypoglycemia (when combined with insulin or sulfonylureas)
- Heart failure (fatigue, dyspnea, edema, sudden weight gain)
- Pancreatitis (persistent nausea/vomiting, severe abdominal pain)
- Allergic reactions (hives, facial swelling, anaphylaxis)
- Kidney problems (decreased function or dialysis)
- Severe skin reactions (Stevens‑Johnson syndrome, blisters)
- Severe joint pain
Side effects of metformin
- Diarrhea
- Nausea/vomiting
- Indigestion and gas
- Headache
- Stomach pain
- Lactic acidosis (rare; tachycardia, fatigue, dyspnea, muscle pain)
- Vitamin B12 deficiency (fatigue, weakness, neuropathy)
- Hypoglycemia (when combined with other antidiabetics)
Warnings & precautions: Januvia
- Allergy to sitagliptin or inactive ingredients
- Severe kidney disease or dialysis
- History of type 1 diabetes or ketoacidosis
- Heart failure or pancreatitis
- Heavy alcohol use
- Pregnancy or breastfeeding (safety unknown)
Shop Medications
Warnings & precautions: metformin
- Allergy to metformin or inactive ingredients
- Renal or hepatic impairment
- Metabolic acidosis or ketoacidosis
- Congestive heart failure
- Age >80 years
- Heavy alcohol use
- Pregnancy or breastfeeding (safety unknown)
Drug interactions: Januvia
Insulin or sulfonylureas (increased hypoglycemia risk).
Drug interactions: metformin
- Carbonic anhydrase inhibitors (acetazolamide, zonisamide)
- Drugs reducing metformin clearance (cimetidine, dolutegravir, ranolazine, vandetanib)
- Alcohol (risk of lactic acidosis)
How they work together
Januvia increases incretin levels to boost insulin release and lower glucagon, while metformin reduces hepatic glucose output and improves insulin sensitivity. Their complementary actions enhance glycemic control.
How to take Janumet / Janumet XR
- Janumet: Twice daily with meals; swallow whole.
- Janumet XR: Once daily with evening meal; swallow whole.
Sources
- Januvia (sitagliptin) tablets, Merck & Co. Last updated 02/2023. Accessed Apr 10, 2025.
- Metformin (Rx). Medscape. Accessed Apr 10, 2025.